<?php
//var_dump($_POST);
$hasError = false;
//变量
$username =$_POST['Username'];   

if(!$username){
     echo"请输入用户名<br/>";
    }

$password = $_POST['Password'];

if(!$password){
     echo"请输入密码<br/>";
     return;
    } else {
        if(strlen($password)<4) {
            echo"密码至少要有四个字符";
            $hasError = true;
    }
}

if(!$hasError) echo "检查通过";


    